Add a curses terminal interface as an alternative to QT

I originally started this for personal use but it garnered support from the linux chan so I decided to continue working on it.

Sorry for the large commits but it's intended to be an (almost) drop-in replacement for the QT interface.

This is a purely functional pull request and should include most major functionality. Over the next few weeks, I'll add more comments, fix bugs, and introduce features which I may have overlooked.

I've never contributed to this project before, so please correct any errors or conventions I need to fix.

The Inbox tab:
![screenshot from 2014-04-30 20 34 53](https://cloud.githubusercontent.com/assets/1038583/2849239/fc3455e8-d0d0-11e3-8bc6-3e26183208eb.png)
The Network Status tab:
![screenshot from 2014-04-30 20 35 39](https://cloud.githubusercontent.com/assets/1038583/2849240/fc4e2478-d0d0-11e3-920f-f36beca63040.png)